Interesting idea. I would add that if you get to this level of sophistication, you should expect users to want to have the possibility to combine the values of probes in DIFFERENT VIs to compute the value of a conditional breakpoint.

As in: "(if my iterative calculation result in VI_1 is smaller than 1) and (if the loop iteration in VI_2 is >100) then pause execution".

This being said, even without this additional level of complexity, with the inherent parallelism of LabVIEW, your suggested functionalities might result in interesting race conditions (something ALWAYS happens during debugging but NEVER otherwise, or inversely)...